Sign up to receive free email alerts when patent applications with chosen keywords are publishedSIGN UP

Abstract:

The invention relates to a pump unit (1), replaceably attachable to a
reusable backend (6) of an injection arrangement (7) for delivering a
liquid medicament, the pump unit (1) comprising a medicament inlet (1.1),
a medicament outlet (1.2) and a pump (2) for delivering the liquid
medicament from the inlet (1.1) to the outlet (1.2), wherein a medicament
container (4) is arranged in the pump unit (1), wherein a fluid
communication between the medicament container (4) and the pump (2) is
establishable when the pump unit (1) is attached to the reusable backend
(6).

Claims:

1. Pump unit, replaceably attachable to a reusable backend of an
injection arrangement for delivering a liquid medicament, the pump unit
comprising a medicament inlet, a medicament outlet and a pump for
delivering the liquid medicament from the inlet to the outlet, wherein a
medicament container is arranged in the pump unit, characterized in that
a fluid communication between the medicament container and the pump is
established when the pump unit is attached to the reusable backend,
wherein the medicament container remains sealed as long as the pump unit
is not attached to the reusable backend.

2. Pump unit, according to claim 1, characterized in that at least one
hollow injection needle for piercing a patient's (P) skin and
administering the medicament or an adapter for attaching the at least one
hollow injection needle is integrated in the pump unit.

3. Pump unit, according to claim 2, characterized in that the needle is a
pen needle or a Luer needle or a micro-needle of a needle array.

4. Pump unit according to claim 1, characterized in that a flow sensor
for determining a volume flow of the medicament is arranged in the pump
unit and connectable to a control unit of a reusable backend.

5. Pump unit according to claim 4, characterized in that the flow sensor
is a thermal sensor or a magnetically inductive sensor or an impeller
sensor.

6. Pump unit according to claim 1, characterized in that the pump is a
peristaltic pump or a gear pump or a diaphragm pump.

7. Pump unit according to claim 1, characterized in that at least one
interface to the reusable backend is provided, wherein the interface is
one of a mechanical, electrical, optical, acoustic, magnetic and wireless
electromagnetic interface.

8. Pump unit according to claim 7, characterized in that the mechanical
interface is arranged for connecting the pump to a drive unit arranged in
a reusable backend.

9. Pump unit according to claim 8, characterized in that the mechanical
interface is a gear or a clutch.

10. Pump unit according to claim 1, characterized in that the medicament
container comprises a septum, wherein the fluid communication is
established by mechanically causing a relative advancing movement of the
medicament container towards a hollow needle for piercing the septum,
wherein the hollow needle is attached to the medicament inlet.

11. Injection arrangement for delivering a liquid medicament, comprising
a pump unit according claim 1 and a reusable backend, comprising a
control unit, a drive unit and an energy source.

12. Injection arrangement according to claim 11, characterized in that
the energy source is a rechargeable accumulator.

13. Injection arrangement according to claim 12, characterized in that
the rechargeable accumulator is chargeable by an external charging device
arranged for holding the reusable backend.

14. Injection arrangement according to claim 11, characterized in that a
user interface for user interaction is arranged in the reusable backend.

15. Use of a pump unit according to claim 1 for delivering one of an
analgetic, an anticoagulant, insulin, an insulin derivate, heparin,
Lovenox, a vaccine, a growth hormone and a peptide hormone.

Description:

[0001] The invention relates to a pump unit, replaceably attachable to a
reusable backend of an injection arrangement for delivering a liquid
medicament. The invention further refers to an injection arrangement
comprising the pump unit and a reusable backend according to claim 11.

[0002] Many medicaments have to be injected into the body. This applies in
particular to medicaments, which are deactivated or have their efficiency
remarkably decreased by oral administration, e.g. proteines (such as
Insulin, growth hormones, interferons), carbohydrates (e.g. Heparin),
antibodies and the majority of vaccines. Such medicaments are
predominantly injected by means of syringes, medicament pens or
medicament pumps.

[0003] A compact small scale peristaltic medicament pump is disclosed in
DE 19 745 999. The pump comprises a delivery head, a drive unit for the
delivery head, and speed control. The pump with the drive unit may be
replaceably attached to a reusable backend in order to maintain a clean
and sterile treatment by disposing the pump off and replacing it with a
clean one after drug delivery.

[0004] WO 2008/040477 A1 discloses an injection arrangement with a
peristaltic medicament pump, wherein the drive unit is integrated in the
reusable backend rather than in the pump unit so the relatively expensive
drive unit does not have to be disposed off every time the pump unit is
replaced.

[0005] It is an object of the present invention to provide an improved
pump unit and an injection arrangement.

[0006] The object is achieved by a pump unit according to claim 1 and by a
injection arrangement according to claim 11.

[0007] Preferred embodiments of the invention are given in the dependent
claims.

[0008] A pump unit according to the invention is replaceably attachable to
a reusable backend of an injection arrangement for delivering a liquid
medicament. The pump unit comprises a medicament inlet, a medicament
outlet and a pump for delivering the liquid medicament from the inlet to
the outlet. A medicament container is arranged in the pump unit and
connectable to the medicament inlet. A fluid communication between the
medicament container and the pump is establishable when the pump unit is
attached to the reusable backend. As long as the pump unit is not
attached to the reusable backend, the medicament container remains
sealed, e.g. by a septum. The fluid communication may be established by
mechanically causing a relative advancing movement of the medicament
container towards a hollow needle for piercing the septum, the needle
attached to the medicament inlet. Integrating the medicament container in
the pump unit improves handling and ergonomics of the pump unit since the
user has to deal with fewer parts. The overall reliability of the
injection device is improved. By keeping the medicament container sealed
before attaching the pump unit to the reusable backend, sterility of the
content, e.g. a liquid medicament is ensured.

[0009] The pump unit may also have at least one hollow injection needle
for piercing a patient's skin and administering the medicament or an
adapter for attaching the at least one hollow injection needle
integrated, thus further reducing the part count.

[0010] The needle may be a pen needle or a Luer needle or a micro-needle
of a needle array.

[0011] The medicament container may have the shape of a standard ampoule
or be a container with a flexible wall.

[0012] Preferably a flow sensor for determining a volume flow of the
medicament is arranged in the pump unit and connectable to a control unit
of a reusable backend thus allowing to control the volume of medicament
to be delivered..

[0013] The flow sensor may be a thermal sensor or a magnetically inductive
sensor or an impeller sensor.

[0014] The pump may be a peristaltic pump or a gear pump or a diaphragm
pump.

[0015] The pump unit may further have at least one interface for
connecting to a reusable backend. The interface may be one of a
mechanical, electrical, optical, acoustic, magnetic and wireless
electromagnetic interface. Preferably the interfaces are arranged to be
easily disconnectable.

[0016] The mechanical interface may be arranged for connecting the pump to
a drive unit arranged in a reusable backend, e.g. the mechanical
interface having the shape of a gear or a clutch.

[0017] The pump unit is one of two major components of an injection
arrangement for delivering a liquid medicament, the other major component
being a reusable backend, comprising a control unit, a drive unit and an
energy source.

[0018] The energy source for the drive unit may be a galvanic cell or
battery of galvanic cells in case the drive unit comprises an electrical
motor. Preferably the energy source is a rechargeable accumulator. The
rechargeable accumulator may be replaceable or chargeable in place by an
external charging device arranged for holding the reusable backend.

[0019] The reusable backend may further have a user interface for user
interaction. This may comprise a dosing and/or trigger knob or wheel
and/or a display, e.g for displaying a dose volume.

[0020] A second septum may be arranged at the medicament outlet. The
second septum is pierced upon attaching a pen needle to the pump unit.
Both the second septum and the pump serve for avoiding delayed dripping
of medicament after injection. By means of the second septum and the pen
needle the pump unit may be used for delivering more than one bolus of
medicament while the interior of the pump unit is kept sterile between
administration of the boluses.

[0021] The pump unit or the reusable backend or the injection arrangement
may preferably be used for delivering one of an analgetic, an
anticoagulant, insulin, an insulin derivate, heparin, Lovenox, a vaccine,
a growth hormone and a peptide hormone.

[0022] Further scope of applicability of the present invention will become
apparent from the detailed description given hereinafter. However, it
should be understood that the detailed description and specific examples,
while indicating preferred embodiments of the invention, are given by way
of illustration only, since various changes and modifications within the
spirit and scope of the invention will become apparent to those skilled
in the art from this detailed description.

[0023] The present invention will become more fully understood from the
detailed description given hereinbelow and the accompanying drawings
which are given by way of illustration only, and thus, are not limitive
of the present invention, and wherein:

[0024]FIG. 1 is a schematic view of a pump unit comprising a pump, a flow
sensor and a medicament container,

[0029] The pump unit 1 is replaceably attachable to a reusable backend 6
(shown in FIG. 3) of an injection arrangement 7 (shown in FIG. 3) for
delivering a liquid medicament.

[0030] The pump unit 1 comprises a medicament inlet 1.1, a medicament
outlet 1.2 and the pump 2 for delivering the liquid medicament from the
inlet 1.1 to the outlet 1.2. The medicament container 4 is arranged in
the pump unit 1 and connectable to the medicament inlet 1.1. A fluid
communication between the medicament container 4 and the pump 2 is
establishable when the pump unit 1 is attached to the reusable backend 6.
As long as the pump unit 1 is not attached to the reusable backend 6, the
medicament container 4 remains sealed, e.g. by a septum (not shown). The
fluid communication may be established by mechanically causing a relative
advancing movement of the medicament container 4 towards a hollow needle
(not shown) for piercing the septum, the needle attached to the
medicament inlet 1.1.

[0031] The at least one hollow injection needle 5 may be a pen needle or a
Luer needle or a micro-needle of a needle array.

[0032] The medicament container 4 may have the shape of a standard ampoule
or be a container with a flexible wall.

[0033] The flow sensor 3 serves for determining a volume flow of the
medicament. It is connectable to a control unit 6.1 of the reusable
backend 6.

[0034] The flow sensor 3 may be a thermal sensor or a magnetically
inductive sensor or an impeller sensor.

[0035] The pump 2 may be a peristaltic pump or a gear pump or a diaphragm
pump.

[0036] The pump unit 1 may further have at least one interface for
connecting to the reusable backend 6. The interface may be one of a
mechanical, electrical, optical, acoustic, magnetic and wireless
electromagnetic interface. Preferably the interfaces are arranged to be
easily disconnectable.

[0037] The mechanical interface may be arranged for connecting the pump 2
to a drive unit 6.2 arranged in the reusable backend 6 for driving the
pump 2. This mechanical interface may have the shape of a gear 1.3 (cf.
FIG. 2) or a clutch.

[0038] The reusable backend further comprises an energy source 6.3 for
powering the drive unit 6.2.

[0039] The energy source 6.3 for the drive unit 6.2 may be a galvanic cell
or battery of galvanic cells in case the drive unit 6.2 comprises an
electrical motor. Preferably the energy source 6.3 is a rechargeable
accumulator. The rechargeable accumulator may be replaceable or
chargeable in place by an external charging device (not shown) arranged
for holding the reusable backend 6.

[0040] The reusable backend 6 may further have a user interface 6.4 for
user interaction. This may comprise a dosing and/or trigger knob or wheel
and/or a display, e.g for displaying a dose volume.

[0041] The pump unit 1 or the reusable backend 6 or the injection
arrangement 7 may preferably be used for delivering one of an analgetic,
an anticoagulant, insulin, an insulin derivate, heparin, Lovenox, a
vaccine, a growth hormone and a peptide hormone.

[0042] For performing an injection a user sets a required target dose at
the user interface 6.4. The required target dose is forwarded to the
control unit 6.1 and stored there. As soon as the user triggers the
injection arrangement 7, e.g by pressing the knob, the target dose is
converted into a flow sensor setpoint and the drive unit 6.2 is started.
The drive unit 6.2 converts the electrical energy provided by the energy
source 6.3 into mechanical energy and forwards it to the pump 2. There
the energy is again converted into fluidic energy causing a volume flow
of the medicament. The integrated flow sensor 3 acquires the volume flow
and forwards measurement values to the control unit 6.1. The measurement
values, particularly when in the shape of increments corresponding to
volume increments may be integrated by the control unit 6.1 and the drive
unit 6.2 switched off upon delivery of the setpoint volume. After
delivery the control unit 6.1 may generate a message for the user to be
displayed by the display unit.

[0043] A second septum may be arranged at the medicament outlet 1.2. The
second septum is pierced upon attaching a pen needle to the pump unit 1.

[0044] The hollow injection needle 5 may be part of the pump unit 1.
Alternatively, an adapter 8 for the hollow injection needle 5 may be
integrated in the pump unit as shown in FIG. 2.

[0045] The flow sensor 3 may be arranged downstream from the pump 2 (cf.
FIG. 3) or upstream from the pump 2 (cf. FIGS. 1, 2).

[0046] When the pump 2 is arranged as a peristaltic pump, the peristaltic
pump may comprise a pump rotor and a pump hose, e.g. a silicone hose. The
pump hose is partially arranged around a perimeter of the pump rotor. The
pump rotor exhibits protrusions, rollers, shoes or wipers for engaging
the pump hose. In this case the pump unit 1 may have a fixing side facing
the reusable backend 6, the fixing side having a recess in the shape of a
circular arc for allowing a correspondingly shaped stop protruding from
the reusable backend 6 to enter into the pump unit 1. When the pump unit
1 and the reusable backend 6 are assembled, the stop supports the pump
hose from an outer side opposite the pump rotor. Thus the protrusions are
allowed to locally squeeze the pump hose against the stop. When the rotor
is rotated the protrusions are advanced along the pump hose thus
advancing the squeezed portions of the hose and the fluid (air or the
liquid medicament) in the hose ahead of the respective squeezed portion
in rotational direction. Consequently, the fluid is forced out of the
medicament outlet 1.2. At the same time a vacuum is created behind the
advancing squeezed portion thus intaking fluid from the medicament inlet
1.1. When the pump unit 1 is not attached to the reusable backend 6, the
pump hose is free to relax because of the clearance in place of the stop
so the protrusions have nothing to squeeze the pump hose against.

[0047] In an alternative peristaltic pump the pump hose may be replaced by
a pump chamber comprising an elongate cavity defined between an
elastically deformable chamber wall and an essentially rigid chamber
wall. The elastically deformable wall and the rigid wall are arranged as
a one-piece part by two-component injection moulding. Preferably the
elastically deformable chamber wall has essentially the shape of a
lengthwise split cylinder and the rigid chamber wall has an essentially
planar shape at least in sections of the elongate cavity, so a pump rotor
in a rotary design or a another squeezing tool in a linear pump design
may press the elastically deformable chamber wall against the rigid
chamber wall without leaving a considerable gap between the two parts.

[0048] In a rotary pump design the elongate cavity and thus the deformable
and the rigid wall are at least partially arranged in a circular arc
shape so as to allow the pump rotor of the peristaltic pump to engage a
considerable length of the elastically deformable wall.

[0049] The term "medicament", as used herein, means a pharmaceutical
formulation containing at least one pharmaceutically active compound,

[0050] wherein in one embodiment the pharmaceutically active compound has
a molecular weight up to 1500 Da and/or is a peptide, a proteine, a
polysaccharide, a vaccine, a DNA, a RNA, a antibody, an enzyme, an
antibody, a hormone or an oligonucleotide, or a mixture of the
above-mentioned pharmaceutically active compound,

[0052] wherein in a further embodiment the pharmaceutically active
compound comprises at least one peptide for the treatment and/or
prophylaxis of diabetes mellitus or complications associated with
diabetes mellitus such as diabetic retinopathy,

[0053] wherein in a further embodiment the pharmaceutically active
compound comprises at least one human insulin or a human insulin analogue
or derivative, glucagon-like peptide (GLP-1) or an analogue or derivative
thereof, or exedin-3 or exedin-4 or an analogue or derivative of exedin-3
or exedin-4.

[0108] A polysaccharide is for example a glucosaminoglycane, a hyaluronic
acid, a heparin, a low molecular weight heparin or an ultra low molecular
weight heparin or a derivative thereof, or a sulphated, e.g. a
poly-sulphated form of the above-mentioned polysaccharides, and/or a
pharmaceutically acceptable salt thereof. An example of a
pharmaceutically acceptable salt of a poly-sulphated low molecular weight
heparin is enoxaparin sodium.